“My interest in Scottish people overseas started way back with my doctoral thesis in the early 1970s,” he told The Scotsman. “I was researching the tobacco connection between Glasgow, the Clyde, Virginia and Maryland. Then I moved into other areas of Scottish history, including urbanisation, sectarianism and society in the Highlands and Lowlands.

“That culminated in a book I published in 1998 called The Scottish Nation, which for two weeks outsold Harry Potter. It was the right time for such a book to be published – it was the year before the Scottish Parliament opened.

“One of my intentions with the book was to bring the treasures of 30 years’ worth of research, from many different scholars, into the public domain. I was absolutely convinced there was demand for a book that was both readable and scholarly.”

Born in Motherwell, Devine has long been fascinated by Scots’ ancient tendencies to travel abroad in search of educational or business opportunities.

“The big issue was the remarkable migration of the Scots – not simply in the last 300 years, but going right back to the medieval period,” he said. “I remember being intrigued by a 12th century French proverb which said: “Rats, lice and Scotchmen – you find them the world over”.

“In relation to the basic population size, which was around one million in 1700, the impact Scots have made globally is remarkable – for good and for ill.”

Scots themselves still underestimate the global reach of the diaspora, Devine believes. “They think in terms of Canada, England, and Australasia,” he said. “But what that leaves out is the period before 1700 and the huge movements to Europe, and the movement to Ulster throughout the 17th century.

“Then there’s the small-scale immigration of people like engineers, physicians, merchants, they’re every where – across Latin America and Asia. Scots engineers and academics were at the very heart of Japan’s industrialisation in the late 19th and early 20th centuries.

“I’ve always regarded Scots as being historically illiterate – not through their own fault, but because there was a whole generation who didn’t learn about country’s past through education. That has changed, of course, but I think the experience of the diaspora provides a very context for where we go now in the post-Brexit period.

“Scots were very powerful in imperial armies of the time as their reputation as soldiers was second to none. One remarkable statistic I pulled up in my research was that between the foundation of the University of Paris in the 12th century and the Reformation, it had no less 19 Scottish rectors. Paris was the Harvard of its day, the leading university in Europe.

“One of the reasons Scots were so successful in developing trade connections was because they cut their teeth in Europe. They used techniques developed through the 12th to 17th centuries to then exploit opportunities in the British Empire thereafter. There is an umbilical chord linking the old migrations to Europe and Ireland to the transatlantic connections.”